Isolated Renal Sarcoidosis: A Rare form of the Disease

Introduction: Sarcoidosis is a multi-system disease characterized by frequent involvement of the lungs. Other organ manifestations without accompanying lung findings are extremely rare. Kidneys may be rarely affected. We present a case, who presented with hypercalcemia, had no lung involvement, and was diagnosed with isolated renal sarcoidosis by renal biopsy. Case: A 76-year-old female patient, who applied with complaints of fatigue and dry mouth, was examined after the examinations revealed increased creatinine and hypercalcemia. Serum creatinine was 4.46 mg/dl, her calcium, parathormone, 1,25-dihydroxy-vitamin D, and serum ACE levels were elevated. She had been examined for hypercalcemia for 5 years, and a diagnosis could not be made. A renal biopsy was performed due to creatinine progression, hypercalcemia and high 1,25-dihydroxy-vitamin D levels. The biopsy was consistent with sarcoidosis-associated interstitial nephritis. Corticosteroids were administered and she responded well. Conclusion: It is crucial to keep extrapulmonary sarcoidosis in mind in patients with hypercalcemia and elevated serum ACE, even in the absence of lung involvement. Although rare, extrapulmonary forms of sarcoidosis can also be seen isolated.